Deteriorating water quality is a serious concern in many developing countries, with severe health consequences especially for children. However, current methods for monitoring waterborne pathogens are often time-consuming, expensive, and labor intensive, which makes them challenging to be implemented in these regions. Toward a solution to this problem, we have demonstrated an electrochemical sensor combined with mobile interface that detects bacterial pathogens suitable for rapid, affordable, and point-of-care water monitoring. The sensor and its mobile interface we developed can be implemented to a wide range of diagnostics. As a proof-of-principle, we successfully detected of E. coli sequences, and mapped the detection results via mobile application.